Cells in normal tissues adhere well to each other. Cells in cancers separate from each other and spread. The problem of metastasis is, therefore, in part, clearly a problem of altered cell-cell adhesion. Understanding of the molecular nature of intercellular adhesion is, therefore, essential to understanding metastasis. In about 38 percent publications, this lab has examined the nature of cellular adhesion and has provided evidence for the role of specific carbohydrates and specific biochemical pathways in the adhesion mechanism. Work proposed for the coming year includes: 1. examination of the growth rate of embryoid vs. single cell form of OTT 6050 mouse ascites tertoma; 2. examination of protease activity in the ascites fluid and in cell homogenates of these two lines; 3. examination of growth and adhesiveness of two lines in the presence of specific protease inhibitors; 4. characterization of molecular weight and subunit composition of the Capelle, Meyer, Sorensen and Oppenheimer (1981) aggregation inhibitory factor; 5. production of fluorescent labeled antibody against the aggregation inhibitory factor (AIF) and utilization of this antibody to determine the cell surface localization of the factor on ascites OTT 6050 mouse teratoma and cultured OTT 6050 mouse tertoma cells. These experiments will help us to understand the reasons for the defective adhesiveness of certain ascites tumor cells.